Sound-reproducing appliance.



H. G. PAPE.

souuo REPBODUCING'APPLMNCL APPLLCATION FILED FEB. 28. N6,

Patented May 28,1918.

HERMAN G. PAPE, OF NEW YORK, N. Y.

SOUND-REPRODUCING APPLIANCE.

Specification of Letters Patent.

Patented May 28, 1918.

Application filed February 28, 1916. Serial No. 80,874.

To all whom it may 0mm.-

Be it known that I HERMAN G. PAPE, a citizen of the United tates, and resident of New York, in the county of NewrYork and State of New York, have invented certain new and useful Sound-Reproducing Appliances, of which the followiiig is a spec-1fica tion. 7

My invention relates to sound reproducing appliances, and various features of the invention relate more particularly to improvements in telephone receivers.

4 An object of the invention is to provide a sound reproducer of compact structure in which the sounds are clearly and accurately reproduced, and in which every compression, reflection, refraction, concentration and which is not; only a physical: strain tothe.

swelling of sound and air are properly accounted for and the sounds reproduced "in the desired strength and in the most nature.

manner. A further object otthe invention is to rovide in a' sound reproducing or receiving instrument, an ear plece having such contour as to satisfactorily meet acoustical requirements, and which moreover is adapted to the physiological requirements of the users ear and is formed tovcomfortably fit ears of various forms and sizes. The ear piece is designed to be held firmly to. the car while in use, so that exterior or surrounding noises are prevented from interfering. This further makes possible definite instructions for its method of use for the attainment of definite and satisfactory results, which has not been possible with the ear caps heretofore in common use so far as applicant. is we f i v fAsi's well known, the users'of telephone hand receivers, without this improvement have been obliged to experiment in their method of holding the receiver to .the ear, so as to avoid the strains from pneumatic concussions, and secure the best results. "On the otherfhand, the central oiiice operators that usefthe head receivers have been forced to useithe receiver firmly pressed by a band was ar a d t me endure Such strains to "delivergood Qandeflicient service at' all t m s 'Variousother features and advantages of the ihvention appear hereinafter. V

":Certain features herein shown are also disclosed in my co ending application Serial No. 874,234, filed ov. 27, 1914.

Referring to the accompanying drawings,

ance with the principles of my invention. Fig. 2 is a front face view of the same. Fig. 3 is a part sectional view of a different form of receiver. Fig. 4 is a fragmentary sectional view taken at the line 4 of Fi 1, showing the rounded form of the ker s in the face of the ear cap.

Referring particularly to Figs. 1 and 2, the telephone receiver comprises a casing includ ing a body portion 5 in which may be mounted the usual electro-magnet and other parts of the sound reproducing mechanism. 'A cap or e'ar piece 6 has a screw threaded Figure 1 is a sectional view of a sound reproducing instrument constructed in accordconnection 7 with the part 5 and also serves to clamp in position the diaphragm 8. The cap 6 is so formed that its greatest diameter which is at the point 9 is located some distance forward of the diaphragm. From this 3. fllhepurposeof this confirmation of the cap is to protect it from receiving knocks or blows on the rearwardly projectin annular 'fiange portion 11 surrounding the ody 5 of the casing.

This flange 11 cannot resist without breaking a knock or blow which could be applied at the point 9 without injury to the cap. Stated another way, the

- tapered form of the cap brings the periphery thereof, at its greatest diameter, opposite the solid front wall orbody of the cap. The receiver can therefore readily withstand the hard knocks to which it may be subjected without the need of unduly increasing the thickness of the rim which is comparatively weak opposite the threads 7 is inclined and harried well awa from the table line and-thus fully protecte The cap series of integral bosses 12 surrounding the cap at its line of greatest diameter, such bosses serving to prevent the receiver from rolling. when lying on a table or other sup port. These bosses may be of such thickness and so'spaced that the receiver when lyin on a flat tableis supported by two ofsai 11, because such rim- 6 is provided with an annular bosses, the body of the cap being held a slight distance from the table as indicated in Fig 3. The thickness however of these projections 12. as well as the distance between them. may be varied.

The provision of means to prevent the receiver from rolling not only serves to protect it from accidents by preventing it vfrom rolling off the support on which it may be laid, but has the following further advantage. Receivers which are liable to roll are frequently set on end with the face of the ear cap resting on the desk or support. The latter is often covered with dust, which is thereby collected on the receiver cap and carried. to the car. This unsanitary procedure is ractically prevented by the provision of the knobs 12 which remove any occasion for standing the receiver on end.

The knobs 12 are preferably rounded to prevent them from scratching or marring the furniture with which they come in contact. They do notadd to the number of parts of a hand receiver, do not interfere with its symmetrical lines, and being formed on the cap are applicable to any receiver on the market using a separable ear cap.

The ear-piece 6 is formed with an inner surface 13 which extends in a continuous curve from the central opening 14: toward the rim of the. diaphragm. That is to say, a radial section of the cap as shown in Fig. 1, presents a convex surface line 13 facing the diaphragm. The inner surface of the cap is quite close to and nearly parallel with the diaphragm near the peri hery thereof, but curves away from the iaphragm toward the central opening 11, the curvature being much more decided near said opening. It will be seen that there is provided between the diaphragm and the inner surface 13 of the cap, a sound chamber 15. The sound vibrations set up by the diaphragm in the chamber 15 are reflected by the convex surface 13 toward the central opening 14 through which they are directed to the car.

A feature of my invention is the provision in sound reproducers of compact construction of means for obtaining the proper swelling or retrai'isformation of the sounds produced, so that these are produced in as natural, clear and lifelike a manner as pos sible; This I have accomplished by providing an annular hollow or groove 16 adjacent to the dia hra 111 seat on the inside of the cap or wa l, w iich is the place where the sounds emitted from the diaphragm are faintest. This arrangement and method of supplyin capacity therefore does not interfore wit the proper concentration of all the vital sounds produced; by the vibration of the diaphragm. The c apaclt v provided by the chamber 16 has the, efl'ect of absorbing the shock or impact'of sound waves produced by sharp or v iolent impulses of the diaphragm, providing an elasticity,

which has an analogy to that of mechanical sllOCk absorbers, such as found, for example, on automobiles.

The capacity provided by the chamber 16, ha the efi'cct ot' absorbin the shock or impact of sound waves produced, by sharp or violent impulses of the diaphragm, roviding an elasticity which has an ana 0g to that of mechanical shock absorbers, w ich are. found for example on automobiles: beides this, the capacity chamber also serves to reduce the tone of the speakers voice to a lower pitch, depending on the depth or ca pacity of the groove. This is a desirable feature as it rectifies in a measure, the high pitch produced by transmitters of the present day through the tightening of nuts or screws on the microphone mechanism, which distorts it and raises the pitch of the voice, the same as an increased tension on a piano wire raises its pitch. The lowered tone of the speakers voice involves a reply in a low tone, thus tending to abate the habit of shouting while telephoning.

It will be understood that the specific form of the groove or capacity chamber may be materially modified, and such modifications where efiective for producing ca acity, without materially decreasing the e ciency or concentrating powers of the sound chamber 15. as by the widening of the groove, or by cutting away or destroyin too much of the contour line 13, are to e considered within the scope of my invention.

The outer face of the cap' 6 comprises a. curved surface 17 extendin from the central opening 31 to the perip ieral portion of the cap. A radial section of the cap (Fig. l) ShOW this surface to extend in a continuous convex curve from the opening 14. The twosurfaces 13 and 1? meet at the opening ll in substantially a hair line forming the periphery of said opening. The surface 17 forms the wall of an outer chamber of considerable depth. formed to fit any ear.

The outer surface 17 is provided with radial kerfs or grooves 18 which, when the cap is held snugly against. the ear, maintain (:on'nuunication between the outside air and the otherwise closed sound chambers within the cap. These kerfs thus prevent or dissipate the pressure waves or variations in the air pressure due to the vibration of the diahragm, which pressure waves are without lhe provision of the kcrfs, focused on the car drum, causing the sounds to be mufiled n -indistinct. and also placing a great strain on the ear drum.

Tin-utility and practical necessity of these vent on the receiver will be more fully up; preciatcd when their function and operation are consideredand compared with'those of the ventsof. one kind or another, whi h are provided in the transmitters of practically all of themillions of telephones now in the field. These vents are generally found on the mouth pieces of the transmitters, (as shown for example in mKPatent No. 822,470) and serve to protect t e transmitter mem brane against undue concussions so as not to increase or hasten the microphone, or otherwise erange the adjustment of theinstrument. The provision of the vents in the receiver, as herein disclosed, serves ina similar manner to protect the ears-of the users against injurious concussions, which is of eater im vortance (to the'public at least, i ,not to t e telephone companies) than the protection of the transmitters. v

Incidentally the vents in the transmitters prevent the sounds from becoming muffled, choked and distorted, when the mouth is placed too close to the mouthpiece, or the part speaks too loudly. Such prevention at t e transmitter is ofv minor importance when the sounds are re r'oduced in the usual receiver and are mu ed'and rendered indistinct by the receiver being held to the ear. The present invention not only prevents mufliing of the sounds that are reproduced by the receiver diaphragm and sent through the ear cap thereof into the ear, but lends utility to that feature of the transmitter whereby is prevented mufiling of the sounds that are sent from the speakers mouth through the mouth-piece of the transmitter into the instrument.-

The kerfs 18 are rounded in cross section, as clearly shown in the enlarged detail view,

Fig. 4, whichconformation is a substantial A improvement on the construction disclosed in my Patent No. 800,675, above referred to. I have proved in practice that when the edge of the kerfs are sharp, as shown in said patent, they produce very sore ears, particularly in cases where the receiver is in almost constant use, or used at frequent intervals, and when: the receiver is quickly laced to the ear with more or less of a rub.

urther, in cases where the cap was con structed with the outer sound chamber shallow, the extension of the, kerfs right up to 'the central opening of the cap caused the sharpedges of the kerfs, when the cap was held against the ear, to be brought against the tragus and antitragus, i. e the cartilaginous or external'opening of the ear. The pressure ofthe cap, and particularly the sharp edges of the kerfs, and the corners produced at the termination of the kerfs in the central "opening pf the cap,-aga'inst these protrudness. 05 In the case of operators head receivers,

acking of the rojections immediately anterior and. posterlor to the meatus auditor-111s exte'rnus,

the importance of, having the kerfs rounded, will be appreciated when it is considered that the head receivers at present in common use, even Without the kerfs, produce irritation and soreness of the ear, often causing the operators to resort toithe use of handkerchiefs, etc., placed between the ear cap and the ear, or other expedients to relieve the car from pressure of the instrument thereagainst. Moreover, "the manufacture, molding and polishing of the caps was rendered difficult by the sharp cdged kerfs extending inward to the central opening of the cap, and involved more careful labor. Also the caps were frequently marred or spoiled throu chipping, particularly where the her s terminate at the central opening of the cap.

The above objections are overcome in the present invention, wherein the kerfs have a rounded contour and terminate or merge into the outer surface 17 of the cap at a substantial distance from the eefral opening 14. The rounded contour of tile wall 17 provides an outer chamber in t e cap of ample depth to accommodate the central protruding portions of the car, so that they bear lightly,-if at all, against the smoothsurface 17, and beyond-the range ofthe kerfs 18. The depth of said outer chamber render; it unnecessary to extend the kerfs to the central opening 14. This results in the further advantage that the inner and outer surfaces 13 and 17 may be molded or shaped to meet in'a hair line at the opening 14, resulting in a higher efiiciency than can be obtained when the wall of the openin itself is of substantial depth.

%rom a hygienic viewpoint, it will be noted that. the kerfs may be readily kept clean,being easily wiped with acloth as they are rounded throughout their length, and merge into the surfacel'i'. The outer convex surface 17 of the cap with its long easy curvature, is well adapted to fit the human ear, whether large or small.

Means for modifying the vibration of the diaphragm, and thus modifying and controlling the sounds produced thereby, comprises a spring, actuated bufier or pressure device. This device may comprise a washer or disk 22 held against the inner face of the diaphragm by'a spring 21 attached to said disk. The spring is connected to a screw 20, threaded through the wallof the casin and adjustable by means of-a head 23. he disk 22 isarrangedto apply pres sure on the inner fape, of thediaphragm so that the latter will 'be' forced outwar ly rather than inwardly, to thereby avoid any liability of the diaphragm 'strikingngainst the actua ting means, such as the 'magnet,

within the casing,l vh1ch means -(notsho rn) may be the same as disclosed in the Patent No. 800.675, before refcrred to. The part 22 which bears against the diaphragm may be made of cork, felt, or other suitable material to prevent scratching or noisy contact.

By adjusting the screw 20, the pressure on the diaphragm may be quickly regulated to secure audibility and purity of tone, and to vary the loudness as ma be desired.

It will be noted that t e ca of the sound reproducer as herein disclose may be used as an ear cap for telephone receivers already in common use. As a separate article of manufacture, the cup presents features of great value.

I find that this cap when attached to an ordinary telephone receiver, will eliminate harshness-and unnatural bynoises, because it produces the proper swelling and the roper concentration of the sounds, and also Because the undesirable interferin echoes are prevented from being retarde in the cap. Familiar voices are distinguished at once and the words, articulations, enunciations, modulations and tone expressions of all voices are faithfully reproduced attheir true and intended value, and are heard even by those quite deaf and Without ear-drums. Seldom does one have to request for matters to be repeated, while the outer convex line concavity of the cap provides a contour which fits almost every car.

In the use of the telephone receiver, the manner in which the sound waves that are emitted by the diaphragm act, and the functionsof the various parts herein presented, may be summed up as foll0ws:--

Sounds emitted by the diaphragm are sent into the centralsound chamber 15 of the cap, where by the aid of the capacity hollow or groove 16, fullness of tone is added to them and, owing to the continuously convex surface 13 the sounds are concen' trated and directed to and through the central opening 14. From this point the sounds strike straight into. the ear, against which is firmly held the outside surface 17'of the cap, provided with the kerfs l8 to prevent air tight inclosure'and permlt radial disvbursement of surplus pressures.

As the sounds enter the outer canal of the.

car they pass freely on into the inner hearing organs, the air pressure which would otherwise be produced w1th1n the ear canal, being dissipated through the open kerfs Thus every intensity, reflecti0n, refract1on and compression of sound and air, have 1n the present invention been properly accountedfor, and mark it a distinct triumph over previous methods, so far asapplicant is aware because natures' hygienic and physioldg cal laws pertaining to the earare maintained throughout, with the receiver held firmly t0 the car as it should be.

The feature of the capacity groove 16 is particularly desirable on excess voltage sysitems of telephony; excess voltage being -and the maintenance or rebuildixi' g of a healthy hearing sense. Eanfatiguin and that trying, straining, nerve and ealth wrecking or a gravatmg condition induced by the use 0 the ordinary telephone re cciver ear piece not possessing the improvements here set forth. are avoided bythe use of this cap.

I wish not to be limited to the exact con struction shown, as modifications way he resorted to without departing from the spirit and scope of my invention.

What I claim is 1. In a sound reproducing instrument, a wall provided with an annular seat for the periphery of a diaphragm, said wall having a central opening, theinterior surface of said wall being of radially convex sound concentrating contour between said seat and said opening and curving away from said diaphragm seat toward said'opening, the curvature of' said sound concentrating surface increasing toward said central opening, said wall being provided with a constantly full open groove or capacity cham ber between the diaphragm seat and said opening, said chamber providing a means to swell or retransform the reproduced sounds a location directly adjacent to the diaphragm seat, said radially convex sound concentrating surface being preferably on] a'hair line distance from the diaphragm a jacent to the groove or chamber;

2. Ina sound reproducing instrument. a wall providing an annular seat for the periphery of a diaphragm, said wall having a central opening, the surface of the wall between said seat and said opening constituting an inverted trumpet bell, or a 'radially convex sound concentrating surface, said surface curving away from the diaphragm seat toward said opening, the cur- -vature increasing toward said opening, said wall formed with a constantly full 0 en fixed groove or chamber facing the iaphragm and providing capacity to permit the swellin or retransformation of harsh sounds, sai hollow or chamber being located directly adjacent to saidseat and between the same and the central opening,

3.- A- sound reproducing instrument as defined in claim 2 and having an exterior New York and State of New York, this25th trum et hell with en'interior oonvex line day of February, A. D. 1916.

soun projecting or sound oon- HERMAN G. PAPE tour merging into the sound concen rat 7 5 surface 0 the interior inverted trumpet be Witnesses:

contour. IDA B. Pun, Signed at New York. in the county of Ion D. Pun. 

